A marine driving device for an overturning conveying device comprises a hydraulic jack and a hydraulic jack base. The bottom end of the hydraulic jack is fixedly connected with the hydraulic jack base, and a hydraulic jack rod of the hydraulic jack is fixedly connected with a mounting plate and externally connected with a gantry. The hydraulic jack base and/or the mounting plate are provided with slide grooves, the bottom end of the hydraulic jack is slidably connected with the hydraulic jack base through the corresponding slide groove, the hydraulic jack rod of the hydraulic jack is slidably connected with the mounting plate through the corresponding slide groove, shapes and sizes of the slide grooves are matched with those of the bottom end of the hydraulic jack and the end of the hydraulic jack rod, and the hydraulic jack and the hydraulic jack rod cannot slide out of the slide grooves. The marine driving device for the overturning conveying device is compact in structure, low in manufacturing cost and long in service life; when a belt carrier is in operation, shaking of the belt carrier is caused by stress nonuniformity resulted from nonuniformity in goods placement, but the slide grooves enable the gantry to have a certain moving space so as to reduce impact on the hydraulic jack due to stress nonuniformity, so that protection of the hydraulic jack is realized; in addition, labor saving, high operation efficiency and high bearing capability are achieved.